A. Field
The invention relates to a heald frame with at least one frame part and with at least one heald carrying rod which is fastened to the frame part.
B. Related Art
In order to achieve high weaving speeds, the aim is to have heald frames with as low a weight as possible. Despite the low weight, they must have high deformation resistance or flexural resistance, so that the healds are not loaded and/or damaged due to deformations of the heald frames. The healds themselves are to be held with play, in particular, in the raising and lowering direction of the heald frames, so that, in the repair of a warp thread break, they can easily be pushed to one side, without the risk of deformations of and/or damage to the healds. The heald carrying rods are to consist of as wear-resistant a material as possible. In practice, therefore, there is provision for the frame parts to be produced from a material of low specific gravity, in particular from aluminum or an aluminum alloy. The heald carrying rods are preferably produced from steel or similarly wear-resistant materials. Since the frame parts, on the one hand, and the heald carrying rods, on the other hand, consist of different materials which behave differently under stress and, in particular, are deformed differently, problems arise in practice.
It is known (U.S. Pat. No. 3,151,634) to provide the frame parts in each case with a flange which is directed toward the opposite frame part and which is reinforced by means of a longitudinal rib. The heald carrying rods, which possess a flat strip-shaped configuration, are fastened to this longitudinal rib of the frame parts. They have, on the side facing away from the longitudinal rib, a wide longitudinal groove, the depth of which corresponds approximately to half the thickness of the heald carrying rod. At a plurality of locations within the longitudinal groove, longitudinal slots are provided, into which are inserted mounting plates which are somewhat shorter than the slots. Spacer plates are arranged on the longitudinal rib of the frame parts. The heald carrying rods and the mounting plates are assigned clamping plates. The entire subassembly is held together by means of rivets which penetrate into the longitudinal rib of the flange of the frame part. It has been shown that a design of this type is relatively susceptible to fatigue fractures which occur due to relatively low, but changing forces. The bores in which the rivets are held on the flange of the frame part are particularly at risk.
It is also known (U.S. Pat. No. 3,754,577) to attach to the flanges of the frame parts two webs which run in the longitudinal direction and between them form a longitudinal groove. This longitudinal groove serves for receiving a middle web of T-shaped heald carrying rods. The middle web of these T-shaped heald carrying rods is held in the longitudinal grooves by means of an adhesive. The manufacture of T-shaped heald carrying rods of this type is relatively complicated and therefore costly, particularly when they are produced from a high-grade material.